Memory devices are utilized for storage of mass data information. Currently, a variety of memory devices have been developed, for example, random access memory (RAM), dynamic random access memory (DRAM), erasable programmable read only memory (EPROM), flash memory, and the like, among which, flash memory are mainstream of nonvolatile semiconductor memories. Currently, according to structures of memory cells, flash memory are classified into stack-gate flash memory and split-gate flash memory, wherein the split-gate memory devices are widely used because of its high programming efficiency without over erasing problem.
However, conventional flash memory devices suffer from wrongly programming due to leakage current on bit lines.
Therefore, there is a need to provide a flash memory device in which programming of certain memory cells may not induce other memory cells to be programmed.